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Hey guys! I have a 1984 Peugeot PSV10N which came with a bolt-on Simplex front derailleur...that is, there is actually a threaded fitting on the right side of the seat tube that the derailleur mounts to, instead of a standard braze-on tab or space for a clamp-on (see pics). My problem is that I want to replace this derailleur with a braze-on Campy FD by way of a clamp-on adapter, but the fitting has a little raised piece which I can't work around (again, see pics). I have been thinking about using a dremel to smooth it down so that I could use the braze-on with the adapter, or maybe even some kind of file. If I were careful and removed as little from the frame as possible, would this have any effect on the structural integrity of the frame? Any help would be really appreciated!

Hey guys! I have a 1984 Peugeot PSV10N which came with a bolt-on Simplex front derailleur...that is, there is actually a threaded fitting on the right side of the seat tube that the derailleur mounts to, instead of a standard braze-on tab or space for a clamp-on (see pics). My problem is that I want to replace this derailleur with a braze-on Campy FD by way of a clamp-on adapter, but the fitting has a little raised piece which I can't work around (again, see pics). I have been thinking about using a dremel to smooth it down so that I could use the braze-on with the adapter, or maybe even some kind of file. If I were careful and removed as little from the frame as possible, would this have any effect on the structural integrity of the frame?

Maybe a little late now, but why do you want to replace it? My experience is that the Simplex FD is every bit as good, if not better, than a Campagnolo FD.

I knew this would come up...the main reason is simply because I want the bike to be completely campy-equipped. I am a complete and utter purist.

Thats the way I thought when I started building up my Paramount -- "Full campy, I'm a purist." But it was taking too long (a too much cash) to get all the parts and, besides, when the bike was new it came with Shimano, so really how pure was I being? So now I have my ode to pre-index bikes ca 1974-1991:

Thanks for the input! I'm going down the same type of road, so we'll see how it goes.

Basically what I want to know is how much you can get away with when dremel meets frame. And in this case, I would only be removing that protruded ring on the fitting, so I'm really thinking that if I did just that it would still be fine. Supposing I do a perfect job, everything would still be the same but just without a 1/4" ring coming off the frame about 1/16th of an inch. Any more takers?

Thanks for the input! I'm going down the same type of road, so we'll see how it goes.

Basically what I want to know is how much you can get away with when dremel meets frame. And in this case, I would only be removing that protruded ring on the fitting, so I'm really thinking that if I did just that it would still be fine. Supposing I do a perfect job, everything would still be the same but just without a 1/4" ring coming off the frame about 1/16th of an inch. Any more takers?

Rather than drew the frame, why not take the dremel to the clamp-on adaptor? Altering the frame is essentially irreversible; FD adaptors are readily available.